If you’re looking for life in this comatose summer at the movies, go directly to Exit Through the Gift Shop, a documentary about rule-breaking street artists that shatters the rules of conventional documentary. The film, which is as much about the filmmaker as his subjects, turns inside-out midway through, at which point the world’s leading street artist — Banksy, a grossly talented Englishman — assumes control from director Thierry Guetta (pronounced Terry). While a certain wariness is called for when directors become their own subjects, particularly in the films of Werner Herzog and Woody Allen, Exit Through the Gift Shop is a film in which nothing plays straight and the very idea of a “subject” is called into question. In this summer of misfit toys and iron giants, what a pleasure to experience a film that dares to try something different. The fact that the project might be an elaborate hoax makes Exit Through the Gift Shop that much more worthy of attention.

The film’s storyline defies summation, or at least challenges the laws of probability. In the beginning there is Thierry, a provincial French shopkeeper who never goes anywhere without a camera. Thierry’s skill set amounts to turning his camera on and always having spare tape handy; to his credit, he tends to shoot indoors and at night. In the process of filming his cousin, a quiet street artist who answers to Space Invader, Thierry develops an interest in a cadre of artists who tattoo small, sophisticated icons throughout the city. On a trip with Invader to Los Angeles, Thierry encounters Shepard Fairey in a Kinko’s — the same Fairey who, as most of you know, created the wistful Obama “HOPE” poster.

Like most street artists, Fairey initially is wary of Thierry, a man whose camera threatens to expose the clandestine nature of Fairey’s work. (Prior to the “HOPE” image, Fairey anonymously posted “OBEY” slogans all across L.A.) But Thierry, a rambling, Rob Schneider lookalike, soon demonstrates both loyalty and stamina, qualities he’ll need as he follows the spider-like Fairey across the rooftops of L.A. Fairey is a daredevil street artist, a thoughtful and intelligent provocateur who relies on ladders and ropes and buckets, each installation an attempt to perfect the pairing of image and urban canvas. It is Fairey who introduces Thierry to Banksy, the most elusive, most respected — and arguably, most gifted — street artist working today.

According to Exit Through the Gift Shop, Thierry is the first filmmaker given access to Banksy, whose face is never shown and whose voice is slightly altered. A Banksy image tends to combine refinement and danger into a single subversive statement — his pastiche of Pulp Fiction depicts Jules and Vincent aiming bananas, not guns — but he is probably best known for his series of picture “windows” on the West Bank barrier wall. Banksy is the first among equals, including the first street artist to command huge sums for his work, and thus he is the first whose work has undergone both widespread vandalism and preservation. It is Banksy who senses the serendipity of Thierry’s arrival as a curator to an art form that is inherently temporary. At Banksy’s urging, Thierry completes the documentary, which Banksy declares unwatchable.

The second half of Exit is about the aftermath of Thierry’s film project. Like a stray dog, Thierry wanders into the world of street art as a practitioner, while Banksy assembles a new film from Thierry’s raw footage. As if all the happenstance prior to this weren’t enough, what follows is the best evidence that Exit is another Banksy prank. Does Thierry find an audience? Does he lose himself along the way? What does Exit say about the way we consume art in the street art era? Exit is a great film not because of its technique, which at best we might called salvaged, but because of the questions it raises about permanence, authenticity and the perils of success.